Field
This disclosure relates generally to semiconductor memory devices, and more specifically, to resistive memory with program and erase verify capability.
Related Art
Memories with resistive storage elements are under development across the semiconductor industry that are geared to replace conventional NVM devices, and in some cases even dynamic random access memory (DRAM) and RAM devices. The resistive memory devices include magnetoresistive random access memory (MRAM), Resistive random-access memory (RRAM or ReRAM), phase-change memory (PCM), among others. Most of the resistive memory devices are implemented in one transistor/one resistive element or one diode/one resistive element memory cell configurations, which provide minimal cell area but exhibit relatively slow read and write performance (e.g., approximately 30 nanoseconds or more per operation). Thus, resistive memory devices are not a viable substitute for much of the SRAM in a higher performance system where read/write operations occur within a few clock cycles unless the time required to perform program and erase operations is reduced. The reliability of the memory cells must be considered as schemes to reduce program and erase times are considered. While increased current and voltages may be used to speed operation, the level of current of a cell dictates the reliability during programming and the level of voltage of a cell dictates reliability during erase. Thus, the minimum necessary level of current and voltage would ideally be used during program and erase operation.